Air cooling is mainly used for cooling an information processing apparatus of an information processing system. Generally, an information processing apparatus is cooled with cold air supplied by an air-conditioner that is taken into the information processing apparatus mounted on a rack.
Japanese Unexamined Patent Application Publication No. 2011-7423 discloses a technology of controlling supply air volume of an air-conditioner such that a temperature of air blown out from the air-conditioner and a temperature of intake air to a rack are the same temperature.